Pile battery fabrication



May 19, 1953 A. FISCHBACH PILE BATTERY FABRICATION Filed Feb. 2, 1951 INVENTOR.

ADOLPH Fl SCH BAOH FIG. I

Patented May 19, 1953 PILE BATTERY FABRICATION Adolph Fischbach, Ocean Township, Monmouth County, N. J., assignor to the United States of America as represented by the Secretary of the Army Application February 2, 1951, Serial No. 209,194

' (Granted under Title 35, U. s. Code (1952),

1 Claim.

The invention described herein may be manufactured and used by or for the Government for governmental purposes, without the payment of any royalty thereon.

This invention relates to a primary deferred action cell of pile type construction using the electro-chemical system magnesium-water-cuprous chloride. A battery of this type, that is particularly applicable here, is described in the patent application of Grenville B. Ellis for a Magnesium- Cuprous Chloride Reserve Battery, of July 31, 1950, Serial No. 176,889.

Deferred action batteries of the magnesiumwater cuprous chloride type have attained considerable importance as meteorological or oneshot batteries due to their high capacity per unit of weight and volume, their excellent operating characteristics even at low temperatures and their case of activation with water,

One of the objects of this invention is to prosec. 266) vide a pile type construction of a deferred-action,-

magnesium-cuprous chloride battery which lends itself to low cost mass production while resulting in a battery of lighter weight, smaller size, and more dependable performance. 7

Another object of this invention is to provide a battery of pile type construction wherein the adjacent electrodes of a series of cells are welded together, resulting in fewer parts, adapted for assembly with fewer operations and being more rugged and simpler in structure and therefore less liable to damage.

These and other objects will become apparent from the following description and accompanying illustration of specific embodiments of the inventive idea.

In the drawings:

Fig. 1 is a perspective view of a complete meteorological battery in a plastic encasement;

Fig. 2 is an enlarged view of a vertical section taken along the line AA of Fig. 1.

The pile type battery shown in Fig, 2 consists of four cells, I, 2, 3 and 4, each cell comprising a cuprous chloride carrying electrode I2, a thin magnesium plate [0 and a spacer I3 of bibulous electrolyte retainin material.

In order to provide a fluid-tight electrical connection of low internal resistance between the individual cells, the thin magnesium electrode is covered on one side with a sheet ll consisting of a layer of conducting and liquid-tight material, as for instance, copper. As shown in Fig. 2, the magnesium sheet 10 and the copper sheet I 1 constitute a unitary bi-metallic plate I! disposed in such a manner that the magnesium sheet III of the plate I! forms the anode or negative elec-- trode of one cell while the copper sheet I l of the same electrode of one cell plate I! faces and elec trically contacts the cuprous chloride electrode of the adjacent cell.

The cuprous chloride electrode, instead of being held against the copper sheet to maintain as low an electrical resistance as possible by contact and pressure, is formed on the grid I5 after the grid has been electrically secured to the copper plate I I. This is easily accomplished by welding or soldering the screen I 5 to the copper plate I l before applying the cuprous chloride paste.

This, in effect serves to simplify the assembly procedure, and the finished structure [5, l6 and I! can be cut into the desired plate sizes to be mounted in stacks. This method requires less handling andinsures contact between the positive, cuprous chloride and the negative, coppermagnesium sheets of the adjacent cells.

The sheet I I may also consist of conducting and liquid-tight material other than copper, provided such material does not interfere with the function of the cell. In other words, the material must be'impermeable to liquids, a goodelectrical conductor and must not be afiected by the chemical and electro-chemical reactions that are going on in the cell. Thus, instead of copper, other metals, e. g., silver, gold, platinum 01' alloys of the same may be used. These metals maybe deposited upon the magnesium sheet I E! by e1ectrolysis or by other suitable methods capable of providing a laminated, closely connected structure of the two sheets I!) and H. To reduce the electrical resistance of the laminated plate I! to a minimum, the contact between sheets Hi and l i should take place upon the whole surface. However, satisfactory contact may be achieved by sew ing or stitching together sheets H and H1, or by crimping their adjacent ends together.

Instead of metals, other materials such as graphite or mixtures of graphite and carbon with or without an agglomerating substance such as resin, tar or synthetic plastics may also be used for providing the conducting, liquid-tight layer II of the laminated plate structure ll. However the material that is chosen must be capable of bonding to the screen l5.

If a suitable mechanical and electrical bonding can be achieved, one of the conductive plastics can be used. Making the sheet H of conductive plastic improves the electric characteristics of the cell and reduces considerably the costs of manufacture. Such conductive plastics may consist of any suitable plastic material containing a conductive filler, as for instance, powdered graphite or metal powder or metal organic compounds. Both the plastic material and the filler must be of such nature as to avoidany undesired reaction with the chemical;products within the cell.

The supporting grid It may consist of a Wire screen of copper, bronze, 1ead, stainless steel, or any other suitable conductive material which does not appreciably affect the electrical characteristics of the cell. The grid licarriesa dried paste [6 of finely ground cuprous'chloride. "Thepuprous chloride paste can be appliedjto"the side of the screen away from the composite sheet'l'l, with or without a suitable binder and water as required, after blanking on" the-edgesof the 'composite sheet. The paste it is of porous-character and may contain an inert conductive material,

as, for instance, finely ground agraphite'or carbon black.

The spacer I3 conventionally consists of paper, .wood pulp,-zmicrop.orous rubber,; g1ass=wool,.rayon (viscose) .felt, orotherliguid retaining rmaterials, inert to the action-of the :substances produced :during'the electro-chemical actions of the cell. The thickness of the spacer l3 :isidesignedto soak up enough electrolyte to allow complete utilization of the active materials of :theelectrodes.

The above described cell elements can be very quickly andsimply assembled in a;pile;;type:bat-

teryby means of an aligning framastacking together first the biemetallic plate I l with the-copper surface face ll down, and .then the spacer I 3 ofbibulous material. resting on thelmagnesium face Hi of the .bi-metallic .platel 'l, the cuprous chloride sideeof -a unit welded to a copper-magnesium plate is placednext to the-spacer l'3, and these latter unitscare-alternated with the spacers until the desired number-of cel-ls-such as l, 2,3 and 4 of Fig. 2 are assembled, and the .stackis terminated with acuprous chloride element. The end cells -I and 4 .areprovided with-electric terminals [8 .and l 9. respectively.

An .outer hull .20 .peripherical-ly surrounds the pile assembly holding the stackedoells 1,2,3 and 4 together undenpressurecontact\While leaving .top. and bottom of these cells open. The outer .hulllil may. consist of polystyrene sheet material or sheets .from various other polyvinyl .resins or the like. Thehull may also-be produced by Winding pressureesensitive cellulosic tape ;(e. v,g., Scotch tape) .peripherically around the pile as- .sembly.

.Priorto providing the outer .hullZB, thesides of the pile structure whichshowthelateral edges of the plates 17 .may be .coated with .a liquidtight seal (notshown) using, for instance,-.pitch, wax .or .any hardenable plastic material which, on -hardening, closes the. openings between the lateral edges of said,plates.l.l.

The .open top and'bottom of the pile mayor may not bev sealed withasuitable plastic material '30 conventionally used .for such purposes. If a seal is provided,.aperturesl3l .must be left Within jthesame :to allow the entrance .of the: electrolyte and, conversely, the escape of .air while the electrolyte is entering the cells. This .may be conveniently done by inserting pins (not shown) in the sealing compound and removing them after hardening of the latter. Top and bottom of thepile assembly may then be covered by a top sheet134 an'd a bottomisheet 35 both made -from polystyrene or any other suitable insulat- ..ing plastic material. Top and bottom sheets 34 and 35 are provided with apertures correspond- :ingtoztheiapertures 3| of the sealing compound 30. The top sheet 34 has openings 38 and 39 (see *Figs. -11a'nc152) .fortherespective terminals I8 and 1'19. "supportingstrips 40 which extend below the hlill'lfl serve .as vilegs to hold the battery in a raised position.

The :assembled battery is activated by imvmersing the same in water which may contain small amounts of hydrochloric acid or sodium 1.chloride:orzothenionizable substances which tend to favorably alter the operating characteristics of the battery. The addition of sodium chloride orother suitable chlorides :to the electrolyte results in .arsomewhat greatericell -.vo1tage andalso brings the voltage -.up "more rapidly, than water alone.

Having described-my invention in connection with specific embodiments, I claim:

A I deferred .action .primary battery comprising a pile of flat cell .unitaeach of said flat cell units consisting of a thin magnesium electrode, a .cuprous chloride electrode, a spacer of bibulous electrolyte retaining material between saidelectrodes, a thin, fiat, electrically conducting plate of liquid-tight material disposed between said cuprous chloride carrying electrode of one cell andthe magnesium-electrodeofthe adjacent cell, said conducting plate and said 'magnesium -:electrode being welded together andsaid conducting plate "and the cuprous chloride carryingelectrode being welded togetherto forma unitary structure constituting at once a :physical barrier with respect =to the electrolyte :and an electrical interconnection of "10W resistance between adjacent cells.

.ADOLPI-I FISCHBACl-I.

References .Citedin theiile of this patent UNITED STATES PATENTS Number Name Date 2,040,255 Gordon May 12,1936 2,322,210 Adams June 22, 1943 2,428,850 Lawson Oct. 14, 1947 2,441,896 Moir May 18, 1948 2,475,152 'Rock Ju'ly5, 1949 2,564,495 Mullen Aug/14,1951 2,582,973 "Ellis Jan. 22, 1952 FOREIGN PATENTS Number Country Date 668,569 France .July 15, .1929 771,012 France July 16, 1934 443,983 Great Britain Mar. .11, .1936 867,151 France July 7,1941

OTHER REFERENCES fMaterials and Methods, :December 1946, pages 1469-4472. 

